This section provides background information related to the present disclosure which is not necessarily prior art.
Large or heavy robotics are used in many manufacturing processes including assembly of automobiles. These machines occasionally require maintenance, such as repair, inspection, or replacement of a gearboxes. Due to the configuration, including weight and weight distribution of such machines, these procedures can be very labor, resource, and time intensive.
Turning to the figures and particularly the first figure, FIG. 1 shows an arrangement 100 arranged by the inventors for the present application. The arrangement 100 includes an example assembly robot 102, being a robot provided by the Fanuc America Corporation. The labor-, resource-, and time-intensive task of changing a gearbox of the robot 102 results from needed setup, use, and teardown of significant ancillary equipment.
The robot 102 can include a base 103, which acts as a counterweight, to forces from the mass and operation of the robot arms, for providing stability. The robot 102 includes a lower joint 104, which can be referred to as a second joint (which the inventors refer to as J2), connecting the base 103 to a first arm 106, which can be referred to as an axis 2 arm (which the inventors refer to as A2).
The first arm 106 connects at an upper joint 108, which can be referred to as a third joint (J3), to a second arm 110. The second arm 110 can be referred to as a third axis, or axis 3, arm (A3).
The robot 102 can be used with any of a wide variety of effectors, or connected items (or end effects) 150, depending on the type of work the robot 102 will be used for.
Example maintenance challenges include changing a gearbox disposed within the lower joint 104. In one method created by the inventors, a crane 120 is used to support parts of the robot 102 to facilitated changing the gearbox.
To change the gearbox using such a crane 120, a large amount of work, time, and space are needed. An existing manufacturing area or cell 130 must be arranged appropriately. Often, pre-existing parts of the cell 130 need to be torn down to create space for the crane 120. Over-head space must sometimes be made by moving existing ceiling structures. Millworkers or riggers need to run the crane 120 and rig it to the robot 102.
As shown, the crane 120 connects by support lines 122, 124 to the upper arm 110 of the robot 102. The crane 120 can also be connected to other parts of the robot 102, such as at or adjacent the upper joint 108, as shown by support line 126. Workers can use one or more lifts or ladders 132 in attaching the rigging and detaching the rigging after the gearbox change.
Once the setup is completed, two or more mechanics perform the gearbox change using the arrangement 100 established.
Further complicating this technique, separating the lower arm 106 at the lower joint 104 from the base 103 cannot generally be done with precision control, and calibration of the robot 102 is typically lost. Electricians and programmers are needed to recalibrate the robot 102 after the joint 104 is reassembled.
In some cases, the cell 130 must be replaced to its prior condition for the subject manufacturing process, requiring further work and time, and so cost. The entire process can require, for example, six or more hours, up to an entire shift of time, sufficient additional space, and multiple mechanics, multiple riggers or millworkers, an electrician, and a programmer.